1. Field of the Invention
This invention generally relates to a vibration damper which has a pneumatic spring component, and a pneumatic suspension system which utilizes such a vibration damper. A pneumatic suspension system can have a number of pneumatic springs between a vehicle frame and at least one vehicle component mounted so that it oscillates in relation to the vehicle frame. This component could be a wheel or a passenger cab, etc. Such pneumatic springs can typically be operated via a control valve for the admission and discharge of compressed air into and out of the pneumatic springs, whereby the control valve can be actuated by means of an actuator.
2. Background Information
A pneumatic suspension system of the type described above is disclosed in German Laid Open Patent Application No. 33 47 435. However, a fundamental problem of this system involves the installation and adjustment of the control valve or the actuator, to set a defined switching position of the control valve as a function of a load condition or of a stroke position of the air spring. Additional space and installation accessories such as brackets, rods, screws etc. are generally necessary for the installation of the externally-mounted level control valve.
In known dampers, during the assembly process, the oscillating vehicle component is usually brought into a defined position relative to the vehicle frame, and the actuator is adjusted or calibrated with the oscillating component held in this fixed position. It can be quite difficult to incorporate this adjustment operation into an assembly line manufacturing process.
Moreover, during operation of a vehicle with a pneumatic suspension system in difficult terrain, dirt and moisture can adversely affect the functioning of the externally-mounted level control valve, and thus of the vehicle itself.